Once World’s Smoggiest, Mexico City Cuts Pollution: How do they do it?

The air in crowded Mexico City killed birds in mid-flight not so long ago. Then ozone levels surpassed the safe zone 97% of the year. Kids once used brown crayons to draw the sky, reports Theresa Bradley (AP), in a city the U.N. named “the world’s most polluted” in 1992. Today this metropolis has cut some of its worst emissions by more than 75% by changing its technology and its laws. Now the “poster child” city for improved air quality, it not only rises above more contaminated capitals such as Beijing, Cairo, New Delhi and Lima but also boasts fewer toxic particles than Barcelona, Prague and 28 other cities.

With the onset of winter ushering in the worst time of year for pollution, Mexico City is committed to spending $3 billion by 2012 to cut emissions further and to expand public transit.

Detection. Detaining. Fining. Environmental police or ecoguarda patrol Mexico City, spotting toxic exhaust from tailpipes. Every day they stop hundreds of offending motorists, issuing $100 fines and even confiscating license plates. This small band is on a mission: “This is the air we all breathe,” one commented.

The city required emissions testing in 1989 and banned old, failing cars from the roads one day each week. They introduced unleaded fuel, required catalytic converters on new cars. A refinery closed and power plants switched from oil to natural gas. Factories moved away and that decentralized some congestion.

Mario Molina, a Nobel Prize-winning Mexican chemist states: “There has been a large improvement, and it’s important to show it could be done. But there’s still a long way to go to get really satisfactory air.

Mexico City seems determined to make that happen.